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A. F. POULE. CALCULAIING MACHINE.

APPLICATION FILED MAY 9, '1917.

Patented Aug. 26, 1919.

2 SHEETS-SHEET I.

65 IIIn Illll/ lll WPI?

A. F. POOLE.

CALCULATING MACHINE. APPLICATION FILED MAYQ. 1911.

Patented Aug. 26, 1919.

2 SHEETSwSHEET 2.

UNITED sTATEs PATENT oEEicE.

ARTHUR .'F. POOLE, KENILWORTH, ILLINOIS, ASSIGNOR TO 'W'AHLl COMPANY, OF

` WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE.

To dll whomc't may concern: i f -Be it known that I, ARTHUR YF.-PooLE, a

ycitizen of .the United States, residing at Kenilworth, in the county of Cook and State of-Illinois, have' invented `certainnew and useful Improvements in lCalculating-Machines, of which the following is a specification. i

My invention is an improvement in lcalculating machines, particularly in that class in which there is an escapement controlledl decimal carriage and an auxiliary 4rack on the carriage, into which rack some of the calculating parts are'- locked during the actuationthereof, for the purpose of prevent- 4ing accidental displacement of 'the decimal carriage during the 'period ofA calculation;

The specific embodiment: of my invention Awhich `I have herein shown is in the wellknown Wahl typewriterv adding and subtracting machine, said machine being de# ten key type, that is, there is present a decimal carriage aged ten' numeral keys, any one of which lmay coperate with a totalizer in any one of the decimal places of said totalizer.Y The totalizer is mounted on a traveling truck, whose motion is controlled by the carriage ofthe typewriter, which in its turn is.

controlled by the usual typewriter escapement. Wahl machine, the typewriter carriage is first tabulated to the highest decimal place' of the number and then the numeral keys are `depressed in order according to the digits vof said'number and after each key is -depressed the typewriter carriageescapes one space, carrying the decimal carriage with it,

and thus vthenumber is inserted into the to-.

talizer digit by digit. I

In the Wahl machine, inorder to prevent misoperation thereof, it is. customary to provide the truck on which the totalizer is mounted with a locking rack and to lock 4parts of the calculating attachment into said rack during the actuation of any of the nu- Specicationof Letterslatent. I

In order to insert a number in this'A oALcULATIiv'MAci-IINE..

Patented Allg. 26, 1919.

Application filed May 9, 1917. Serial No. 167,464. Y

writer carriage and its connected truck during the insertion ofa number into the to talzer. In the Wahl machine the escape- `ment rack which controls the escapement of the carriage is usually located in the' rear part of the carriage and the truck carrying the totalizer and the locking rack just referred to is locatedon the front side of said carriage. The members which coperatie with these racks are, of course, rotatably `mounted on the frameworkjof the ltypewriter. In .consequence of this arrangement there is present the condition of having the rtypewriter carriage located by the escapement rack at the rear of the carriage andv also having the carriage located by the locking' rack at the front of the carriage. This condition necessitates very accurate work,- manship, both in the spacing of the escapement rack at the rear of the carriage and in the spacing of the locking rack at the front( of the carriage. Furthermore, this construction necessitates very accurate workmanship in the maintaining of the typewriter carriage bearings in proper condition so that these bearings will permit of no lost motion between. the carriage and the typewriter framework.

It is necessary, from consideration of wear, to make the escapement rack of somewhat heavy metal-.and to make this rack hard. It is well knownthat when a piece of steel of the size of.I an' escapement rack is hardened that there is a certain amount of distortion, due to the unequal expansion of the'metal during the hardening process.

and it. is therefore veryl diiiicult to make the.

`act spacing* of the teeth of these racks.

Even if thel racks -vare made absolutely accuseV rate when soft. they will distort enough during hardening to have, in extreme., cases, as'

sandths of an inch between the position of corresponding teeth on the two racks. Practically the only way to get these racks in absolute registration is to take one of them,

l'great a difference as from five to ten thoupreferably the 'escapement rack, as a stand- -I ard and grind the teeth of the locking rack to match the teeth of the escapement rack.

In practice the cost of adjusting these two ros racks to each other is so great as to be'cominercialljy? prohibitive and, as usual in such cases, a compromise is adopted; that is, the teeth of the escapement rack are made hard and .the teeth of thexlocking rack are left soft, and by operating the machine for a time before it is put on the market, the soft teeth of the locking rack become worn into correspondence with the hard teeth of the escapement rack.

connnercial disadvantage of this practiceis that the locking rack being necessarily soft, does not wear as long as it would if it were possible to harden said rack and thus l the effective life of the machine is materially lessened.

Another difficulty which arises fioin the fact of the escapement rack and the locking rack not being in exact correspondence is that in case the locking rack as a whole is slightly out of its correct adjustment in respect to the typewriter rack then, when the numeral key is depressed consequently throwing a locking member into this locking rack, the whole typewriter carriage is moved bodily a short distance, therebythrowing an undue load upon the numeral key and making the actionof the machine harder than would be the case if theescapement rack and locking rack' were in perfect adjustment.

It' is the object of my invention to provide a structure for calculating machines of the type of the Wrahl machine, (which throughout this specification I shall take as a typical example, although my invention is by no means confined to use with the Wahl machine) which will allow the use of an escapement rack and a locking rack which are not in perfect lcorrespondence or adjustment, and, as a result, of allowing the use of vthese practically inaccurate vracks, permitting both of the racks to be made hard, thereby insuring greater wear and also to entirely avoid the necessity of replacing two rac-ks in case one ofthem should be damaged or of wearing one of the racks into correspondence with the other, as hereinbefore described.

A further object of my invention is to greatly clieapen the construction Iof machines of this character and to minimize the undesirable results of either the escapement My invention may be best understood by reference to the accompanying drawings, in which- Figure 1 is a sectional view of some of the calculating parts of a Wahl machine;

Fig. 2 is a detail 'view of a certaintloating locking member and master wheel employed therein;

Fig. .3 is a detail View,- partly 'in section, taken along the line 3-3 of Fig. 1;

Fig. 4 is a side elevation of a typewriter upon which my invention is mounted, and

Fig. 5 is a diagrammatic top view of a typewriting'adding machine embodying my herein describedinvention.

Similar figures of reference serve to identify like parts in all the views.

As before noted, while I have described the preferred embodiment of my invention on a lVahl machine, yet this machine is only taken 'because it is in a manner typical of one Aclass of machines to which my invention may be advantageously applied. ,j

Referring to Figs. 1 and 4, I have shown a typewriter 10, on which is mounted the usual carriage 11, servingto support the platen 12. On the carriage is mounted theusual escapement rack 13, in mesh with which is a spur gear 14, rotatably mounted in a bearing lon the framework of the machine. Attached to the spur gear 14 and rotating therewith are the usual Remingtony escapement wheels 17 and 18, which are engaged by a dog 19, rocking on a pivot 2O in the framework of the machine and having rigid therewith a crank 21, which is connected by a pull rod 22 to an arm 23, mounted on a rocker 24, and having an arm 25 rigid therewith. A ,universal bail 26 extends lunder all of the typewriter keys, in-

cluding numeral keys 27, and is supported from the arm 25- by a link 28. A similar arm 25 and supporting link 28 y(not shown) serves to support the bail 26 at the other side of the typewriter and thus it will he readily seen that depression of any of the numeral keys 27 will, by reason of the chain of. mechanism just described, result in the rocking of the escapement dog 19. The typewriter carriage 11 is urged to the left by the customary tape and spring (not' shown) and as za. result thereof will be advanced step by step upon operation of` the keys 27.

The usual step advance of the typewriter carriage is one-tenth of an inch@ For ordinary typewriter work this need bev only approximately correct. It may vary one to two per cent. either way without being noticed. Obviously' the exact location of the typewriter carriage depends on (1) the accuracy ofthe rack 13, theI accuracy of Ithe gear 14 `and the accuracy ofthe gears 17 and 18. Errors in any of these pai'- ticulars or in all ot them may all operate in y the same direction, or may operate to offset each other. However, it willbe vreadily apparent. that the maintenance of an exact spacing of one-tenth of an inch in the stepbyystep motion of a typewriter carriage is a matter of quite `a good deal of mechanical` diiiiculty.

Considering now the calculating portion of a machine, there is a totaliZer-29, which is mounted on a truck 30, which is connected at either end to the typewriter carriage by brackets 31,32. This truck is supported in a casting. 33, attached to the front' portion ofthe framework of the typewriter. In this casting are mounted rollers 34, 3 5, which serve to maintain 'the truck 30 in :its proper here, except to note lthat therevis present position.

in the patent to Webster, No. 968,103, dated August 23,v 1910, and therefore need not be described here. Mounted.' on Athe truck 36 .is the locking rack 36, whose functions will hereinafter be described' vThe truck 30, as before noted, serves as a support for the Atotalizer 29. .The parts of this totalizerv are shown in detail in the sectional view of .Fig. l, and since these parts are described in several. issued patents,

particularlytheone to 'Wahl supra, itp'will not be necessary to describe these parts in the totalizfer a series of carrying wheels 37, which are rotatably mounte'dron a shaft 38, and are acted on in succession by a master wheel shaft 40.

The numeral keys 27. of the-typewriter 10 are connected bypull rods 41 tocertain Amechanism in the actuator thoroughly de- 104 scribed in the cited Wahl patent. 4Depression of any typewriternumeral key 27 results in the rotation of the master wheel 39a differential 'amount and the rocking of a-'master dog 42,'which is pivoted on a shaft 43 in the lframevorkof the actuator. -Thecycle of operations of these two parts,

that is, the vmaster wheel39 and the dog 42, is as follows: Upon the 4rst part of the This construction of the truck and its mounting is described in great detail Rigid with the master dog 42- and therefore also rocking on the shaft 43 is a locking dog 44, which is adapted to engage in the teethof the `locking rack 36. lSince it 4will be remembered that the master dog 42 is held in its displaced position during the differential rotation of the master wheel 39, itis evident'that the truck 3 0 and its thereon mounted totalizer 29v will be held vimmovable asfar as the framework of atypewriter is concerned during the 'differential rotation of the master. Wheel..

I have explained the foregoing mechanisms in only a somewhat general way, since they are well known inthe Wahl adding machine and have been described in numer- `ous patents to Wahl and others;

I shall nowv describe the mechanism'which vis .peculiar to-my. invention: I

Referring particularly. to Fig.v 2,/ it will be seen that the master dog 42 is mountedy L ona shaft 43 and that this shaft in its turn 39, mounted on' a rotatable depression of the typewriter key 37 the master dog 42 is rocked on its-shaft`43 in a co'unterclockwise direction (Fig. 1). The

-dog performs certain operations 'in the totalizer which need not be herein specified, and after this rocking of the dog has taken place the master wheel 39 is rotated a differential amount, depending upon thefparticular numeral key 27, which has been opa erated. Before the key has completed its down stroke and after the completion of the differential rotation of the master wheel 39, the master dog 42 is released and reis mounted in ytwo plates 45 and 46, which arergid to the framework of the machine. The shaft 43 is'made to have considerable endplay or lateral motion between the plates 45 and 46, since 1t will be noted in Fig.- 2 that' the length of the shaft 43 between its shoulders is somewhat less than the distance between-said plates. The lockin'g dog 44 is rigid with the master dog 42,

`and also with a fork 47, the prongs of which embrace the master wheel 39. The

master wheel is rigidly mounted on a shaft 48,l which turns betweentheside plate 45 and a plate 49, also rigid to the framework, and it will be yobserved that, asin the case of the shaft 43, the distance between the shoulders' of theshaft 48 is somewhat less than the distance between the two plates in which said shaft has a bearing. In practice, I have found that giving these shafts .a lateral motion of -twenty-thousandths of an inch is sufficient and will take care of the greatest discrepancy which l have found' between any two racks.

Slidably mounted on the shaft 48 is the i 59 inthe direct gear 50. The rocker 55 turns to its original position.v Thev typey .writer carriage then lescapes and the master wheel 39 comes into mesh with the totalizer gear 37 of neXt lower denominationj itself is pivoted to the framework on the vstudV screw' 60.v Shifting of thel reverse shaft 54 will reverse the direction of rota-- tion of the vmaster wheel-39 consequent upon the depression of any of the numerals. .It

is bythis means that thefmachine maybe made-to either atd or subtract, or when thev issued September 12, 191,6.

The locking dog 44 is provided with a beveled end 61, and-the teeth of the locking Arack 36 are beveled as shown at 62.

The operation of my improved machine is as follows: The typewriter carriage 11 is located by the escapement dog 19 into some position and since the truck is connected to the typewriter carriagev 11 -by the brackets 31 and 32, this truck is located in a definite position also. not coincide with the locking dog 44, being exactly under the 'space between two consecutive teeth of the locking rack 36. However, when a numeral key 27 is depressed, the beveledA end v61 of the locking dog 44 will contact with the beveled end of the teeth 62 and since the shaft 43 has motion between its side plates, the locking dog 44 will locate itself in a position between the teeth 62 of the locking rack 36. The locatingof `the locking dog 44 will also result in the locating of the two actuator members which contact with the totalizer, that is, the master w-heel 39, since this wheel will be located by the fork 37, 4and the master dog 42, whichvwill be located by the fact of its being rigid with the locking dog 44. The

totalizer itself is, of course, located on the truck by contact of the latch 63 with a locating rack 64 on the upper side of the truck. And the amount of variation between the loeating rack and the locking rack 42 will never be great enough to produce an interference between the master wheel 39 and -the totalizer wheels 38 on either side of the either direction (such shifting beingpermitted by the lateral shifting of the shafts 43 and 38) yet the Voperative connections between the master dog 42, the master wheel 39 and the totalizers, will not be changed and therefore no interference will result.

It is thus evident that by the simple eX- edient of providing. the locking dog so that 1t will locate itself into the truck, instead of having the locking do'g not laterally shiftable in the framework and locating the truck (as has been the construction heretofore) avoids the necessity of anyv exact correspondence betweenl the escapement rack 14 This position may or may by saying that the typewriter carriage and the truck 30 are first located in a position dependent entirely upon the action of the typewriter escapement. Then when the numeral key of the typewriter is first operated, the calculating parts locate themselves into a position depending upon the position of the typewriter carriage 11. By reason of the simple' expedient herein described, it is not necessary to have the racks 36 and 14. in exact correspondence and there is an allowable variation of twenty thousandths of an inch, that is, ten thousandths on either side of the normal. position. This standard of accuracy can be easily and cheaply maintained in commercial machines.

I have also, bv my herein described invention, obv-iated the. fault which will arise even xwith perfect racks 36 and 14 of having the entire typewriter carriage shifted bodily by the numeral keys in case the truck 30 becomes slightly out of adjustment. The

parts which are located bythe coperation of the locking dog 44 with the locking rack 36 are only the two shafts 43 and.48 and these shafts are very light, indeed of practically negligible weight in comparison with the weight of the typewriter carriage itself.

Many modifications and variations may be made from the precise structure herein shown withoutdeparting from the spirit of my invention. As before noted, I have described as the preferred embodiment of my invention in its application to the wellknown yVahl adding machine. However, this particular machine is taken simply as a type. There are quite a number of calculating machines on the market and which have been proposed in which my herein described invention would be of great advan tage. I believe I am the first to show a decimal carriage carrying calculating instrumentalities and controlled by an escapement and providing means to locate other calculating devices in accordance with the position of said carriage before these devices perform their function upon the instrumentalities mounted on the carriage and I wish to claim the same broadly.

Having thus described my invention, I claim:

1. In a'calculating machine,r the combination of' a noving carriage, means to locate said Vcarriage ina series of predetermined positions, calculating instrumentalities carried by said carriage, other calculating devices iioating in the framework adapted to coperate with said instrumentalities, and mean's to locate said devices in a position predetermined by said decimal carriage before said calculating operation is initiated.

2. In a calculating machine, the-combination ofv a decimal carriage, an. escapement for said carriage, a set of keys operative on said escapement, and means to lock said car'- riage in position during thel depression of any of said keys, said lockin means floating in the framework to allow or inaccuracies in said escapement rack.

3. In a calculating machine, the combinationof a decimal carriage, a set of numeral keys, an escapementfor said carriage con' trolled by saidmkeys, a rack forming part of said escapement, a totalizer, a master wheel to `insert' numbers therein, a locking device adapted to lock said decimal carriage dur-- ing the insertion' of numbers by said master Wheel, said locking device being adapted to float in the framework, whereby the effect of inaccuracies in` saidescapement rack may be avoided. i

4. In acalculating machine, the combination of a' decimal carriage, a set of numeral keys and yan escapement for said decimal carriage including a rack, said escapement being operated upon depression Of-any ofv said numeral keys, a totalizer, means to insert numbers therein, the relation of said' y -number-inserting mechanism.

' 5. In a calculatingmachine, the `combination of a decimal carriage, aset of keys,

an escapement for-said carriage controlled by said keys?, said escapement including a y rack as one of its parts, Ea second rack at-Y tached to said carriage, inreans adapted to lock said carri'ageto the framework of the machine during'the operation of any of said numeral keys, said locking means engaging said second rack andv said locking means being provided with a floating bearing'- l whereby it may adjust itself toany discrepancies between the two racks..

6. In a calculating machine, the combination of a' decimal carriage, a set of nu- ;nieral keys, escapement 'mechanism includ- .,ing a rack, said mechanism beiiigoperated i by any of said numeralkeys, a locking rack attached to said carriage', a dog adapted to 1 engage the teeth of said locking rack thereby rendering the carriage' immovable dur# ing the operation of' any of said numeral keys, and a floating bearing for said dog-'in the'framework of themachne whereby said dog may accommodate 'itself to a lack'of\.

correspondence between 'saidracks z 7. In a calculating mach ing rack.

keys, anescapeme-nt for said carriage adapted to be actuated by said numeral keys, said es capement mechanism including a rack as one of its parts, a second rack attached to \said carriage, a locking dog adapted to be actuated by any of said numeral keys to engage said locking rack and-thereby lock the decimal carriage during the actuation of any 'of the numeral keys, and a shaft mounted in the framework of a machine and upon which said dog is mounted, said shaft being provided with lost motion in its bearings whereby the locking dog may accommodate itself to a lack' of correspondence between- `the two racks.

.8. In a calculating machine, the combination of^a decimalcarriage, escapement mechanism for saidcarriage .including Ia rack,- a set of keys,` means to operate said escapement mechanism consequent upon the actuation of any lof said keys, aj locking rack also mounted 'on ,said decimal carriage, a

totalizer, number-inserting means therefor.

controlled by said keys, said totalizer and number-inserting means having their rela'- tive position determined by said decimal carriage, a locking dogadapted to enter the teeth of saidv locking rack upon the actuation of any of said numeral keys and lock said decimal carriage", a floating bearing for said locking dog, and connections between said locking dog and said numberinserting means whereby the number inserting means will take a position determined by the engagement of said locking dog` with said lock- 9. In a typewriter computing machine, the combination of a typewriter carriage, a

,set of keys, an escapement mechanism governing' the position of lsaid typewriter carriage, said escapement mechanism including a rack and beingfcontrolled by any of said keys, a `locking rack, means to move said i lo'ckinov `rack insynchronism with themotion o? said typewriter carriage, and a lo'ckv ing'dog slidably mounted in the framework of the machine and adapted to engage said locking v'rack upon the actuation of any of -said 'numeral keys.

l0. In a typewriter calculating machine, the combination ofv a set of keys, .a typewriter carriage, escapementmechanism therefor includinga rack, said e'svcapement mechanism being adapted tobe operated4 upon the operation ofv any of said keys 'and thereby advance said carriage 'step Iby step,`

a locking rack upon said carriage, a dog adapted lto engage the teeth of said locking rack, connections vbetween said key "and said .dog to abtiiate the same to engage the locking rack upon the actuationofany of said numeral keys,`and a shaft for said do saidv shaftvbeing rotatably mounted inl the ramework and' having slight lateral motion-thereto whereby the position of said dog will' adjust itself to a lack of correspondence between the escapement and locking racks.

l1. In a typewriter calculating machine, the combination o'f a typewriter carriage, a set of keys, an escapement mechanism controlled by any of said keys and including an escapement rack, a lock-ing rack moving synchronously with said carriage, a totalizer, number-inserting mea-ns for said totalizer, a locking dog adapted to enter the teeth of the locking rack ,and thereby prevent relative motion between the totalizer and its number-inserting mechanism during the insertion of a' number, said' number-inserting mechanism and said locking dog havinga slight lateral motion with respect to the framework of the machine whereby the typewriter carriage is located in respect to the framework during the insertion of a number, and the number-inserting mecha- 'anism and locking dog may adjust themselves to a lackof correspondence between the locking rack and the escapement rack.

12. In a typewriter calculating machine,

"the combination of a typewriter carriage, a

.set' of numeral keys, an escapement mechanism including an escapement rack and adaptedrto be governed by any of said numeral keys, a totalizer traveling synchronously with said typewriter carriage, a master. lwheel mounted in the framework of the machine and adapted to insert numbers in Vsaid wheel is mounted, said'shaft being both rotatably -and slidably mounted vin -the frameworkof a machine, a locking dog also' rotatably andslidably mounted in the framework of a machine, a'ndmeans connecting said master wheel and locking dog whereby the lateral Amotion 4of one will `produce lat- .lateral motion of the other.

eral motion'of the other.'

le. In a calculating machine, the combination of a locking dog slidably and rotatably mounted in the framework, a master wheel also slidably and rotatably mounted in the framework, and a connection between said locking dog and said master wheel such that lateralmotion of the one will produce 15'. In a" calculating machine, the combination of a traveling rack, a locking dog adapted to enter said rack, said locking'dog being rotatably and slidably mounted in the framework of a machine, a master wheel mounted rotatably and slidably in the framework of the machine, and a connection between said master wheel and said locking dog'to the end that said master wheel and said locking dog will both take aposition as determinedbythe engagement of said locking dog with the teeth of said rack.

16. Ina calculating machine, the combination of a decimal carriage, a totalizer mounted on said decimal carriage, a -locking rack mounted on said decimal carriage, a locking dog adapted to engage said rack, a master wheel ada-pted to `insert numbers inl said totalizer, and connections between said locking dog and said masterwheel such that said locking dog and master wheel will assume a position relative to said totalizer as determined by the engagement of said lock- 85 ing dog with said locking rack.

'17'. In a calculating machine, 'the combination of a traveling totalizer, a locking f rack traveling with-said totalizer, alocking 'dog slidably and' rotatably mounted'in the 9i) framework of themachine and also adapted to engage said totalizer, a master wheel adapted to insert numbers in said totalizer, a set' of numeral keys, connections between said nulneral'keys and said lockinor dog, a 95 v l master wheel whereby actuation oA any of said keys will first engage said locking dog with said rack and then rotate said master wheel a differential amount, said master .rwheel and locking dog being so connected -that said master wheel and locking dog will both take a position determined by the engagement of said locking dog with said locking rack.

18. In a typewriter calculating machine, the combination of an escapement rack, a locking rack and a floating dog adaptedl to engage said locking rack.

19. In a typewriter calculating machine, the combination of an escapement rack, a locking rack, a totalizer whose position isdetermined by the position'of said locking rack, a floating dog adapted toengage said locking rac-k, a floating master wheel and a connection between 'said dog and saidmaster wheel whereby both dog and master wheel will take a i osition determined bythe contact of said loc zing dog with said locking rack,

20. In a typewriter calculating machine, the combination. of a spring-actuated carrlage, an escapement rack controlling the position -of said carriage, a locking rack moving with said carriage,y and a floating dog adapted to engage said lockingrack.

21. In 'a typewriter calculating machine, the combination of a spring-actuated carmage, an escapement rack controlling the position of said carriage, a locking rack connected to said carriage, a totalizer also connected to said carriage, a locking dog slidably mounted in the framework and adapted to engage said locking rack, a master wheel slidebly mountedv in the framework and adapted to engage Said totalizer,

'of Mey, A. D. 1917.

and means connecting said master Wheel and locking dog to locate both of them in a' po sition determined by the engagement of Said locking dog with 'Said looking rack.

Signed at Chicago, Illinois, lthis 5th day ARTHURF. POOLE. 

